1. Field of The Invention
The present invention relates to the field of separating copper (II) from used industrial catalysts which contain copper (II) and other metals. More particularly the present invention relates to the field of separating copper (II) from chromite in materials containing both metals.
2. Description of The Prior Art
Large quantities of catalysts containing copper (II) and chromite are used in many industrial processes, particularly for hydrogenation. These catalysts eventually become poisoned and must be discarded. Millions of pounds of such catalysts are discarded each year in the United States. Not only does the disposal of this used catalyst, typically in landfills, lead to environmental problems caused by leaching of the metals, with eventual contamination of groundwater, but disposal of these catalysts also represents a substantial economic loss. Both copper and chromium have considerable value, with copper selling for approximately $0.75-$1.00/pound and chromium being of at least comparable value.
However, there currently exists no commercially viable process for the separation of copper from chromite in a catalyst containing both copper and chromite. Thus, there is a need for a simple and economical process that can be used to separate copper from chromite and recover copper. Preferably, such a process should also be able to recover the chromite as chromium metal.